Lidar system, method for controlling lidar system, and vehicle

Abstract

The invention discloses a laser radar system, a laser radar system control method and a vehicle, and belongs to the technical field of vehicles. The laser radar system comprises a transmitting module which is used for transmitting laser pulses with different amplitudes to a target space in a plurality of measurement periods; and the receiving module is used for receiving the laser pulse reflected by the target space in each measurement period, and obtaining distance information of a target object in the target space based on the laser pulse received in each measurement period. The near-distance and far-distance detection capability and precision can be improved at the same time, the dynamic range of the radar is enhanced, and the distance information of the target object in the target space is obtained more accurately.

Description

Technical Field

[0001] The present application belongs to the field of vehicle technology, and in particular relates to a laser radar system, a control method for the laser radar system, and a vehicle. Background Art

[0002] LiDAR is a sensor that can generate three-dimensional spatial point clouds. Due to its high-precision, high-resolution three-dimensional imaging capabilities, it can provide more assistance to high-level intelligent driving systems and may become an indispensable sensor for high-level intelligent driving.

[0003] However, current lidars typically have a small dynamic range, making it difficult to achieve both short-range and long-range measurement accuracy. Summary of the Invention

[0004] This application aims to solve at least one of the technical problems existing in the prior art. To this end, this application proposes a laser radar system, a control method for the laser radar system, and a vehicle that can simultaneously improve the detection capability and accuracy of both short-range and long-range radars, enhance the radar's dynamic range, and obtain more accurate distance information of target objects in the target space.

[0005] In a first aspect, the present application provides a laser radar system, comprising:

[0006] A transmitting module, used for transmitting laser pulses with different amplitudes to the target space within multiple measurement cycles;

[0007] A receiving module is configured to receive the laser pulse reflected by the target space in each measurement cycle, and obtain distance information of the target object in the target space based on the laser pulse received in each measurement cycle.

[0008] According to the laser radar system of the present application, laser pulses with different amplitudes are emitted by the transmitting module in each measurement cycle. Some laser pulses have greater energy, and some laser pulses have less energy. Laser pulses with greater energy can still have greater energy after propagation attenuation, so that they are easier to be captured by the receiving module, which can improve the long-range detection capability and accuracy. Pulses with smaller energy can make the reflected laser pulses not exceed the dynamic range of the receiving module, thereby reducing saturation, which can improve the close-range detection capability and accuracy, and realize the enhancement of the radar dynamic range. The receiving module obtains more accurate distance information of the target object in the target space based on the laser pulses received in each measurement cycle.

[0009] According to one embodiment of the present application, the transmitting module is used to transmit the laser pulses with increasing amplitude and / or decreasing amplitude to the target space.

[0010] According to an embodiment of the present application, the measurement delay of each measurement cycle is different, and the measurement delay is the time interval between the moment when the transmitting module transmits the laser pulse and the moment when the receiving module receives the laser pulse.

[0011] According to one embodiment of the present application, the receiving module is used to form histogram data based on the laser pulses received within the measurement period, and based on the moment when the transmitting module transmits the laser pulse, the histogram data within each measurement period is interleaved and superimposed to obtain a target histogram, and the distance information is obtained based on the target histogram.

[0012] According to one embodiment of the present application, the transmitting module is used to transmit the laser pulse at a random moment in each measurement cycle, and / or the receiving module is used to receive the laser pulse at a random moment in each measurement cycle.

[0013] According to one embodiment of the present application, the receiving module is used to adjust the reverse bias voltage of its own photodiode during the process of receiving the laser pulse.

[0014] According to an embodiment of the present application, the reverse bias voltage changes in the same pattern in each measurement cycle.

[0015] According to one embodiment of the present application, the laser radar system is a single photon avalanche diode laser radar system.

[0016] In a second aspect, the present application provides a control method for a laser radar system, the method comprising:

[0017] Controlling the transmitting module to transmit laser pulses with different amplitudes to the target space within multiple measurement cycles;

[0018] The control receiving module receives the laser pulse reflected by the target space in each measurement cycle, and obtains distance information of the target object in the target space based on the laser pulse received in each measurement cycle.

[0019] According to the control method of the laser radar system of the present application, laser pulses with different amplitudes are emitted by the transmitting module in each measurement cycle. Some laser pulses have greater energy, and some laser pulses have less energy. The laser pulses with greater energy can still have greater energy after propagation attenuation, so that they are easier to be captured by the receiving module, which can improve the long-range detection capability and accuracy. The pulses with smaller energy can make the reflected laser pulses not exceed the dynamic range of the receiving module, thereby reducing the saturation phenomenon, which can improve the close-range detection capability and accuracy, and realize the enhancement of the radar dynamic range. The receiving module obtains more accurate distance information of the target object in the target space based on the laser pulses received in each measurement cycle.

[0020] According to an embodiment of the present application, the measurement delay of each measurement cycle is different, and the measurement delay is the time interval between the moment when the transmitting module transmits the laser pulse and the moment when the receiving module receives the laser pulse.

[0021] According to one embodiment of the present application, the method further includes:

[0022] The receiving module is controlled to adjust the reverse bias voltage of its own photodiode during the process of receiving the laser pulse.

[0023] In a third aspect, the present application provides a vehicle, comprising:

[0024] A laser radar system as described in the first aspect above.

[0025] According to the vehicle of the present application, laser pulses with different amplitudes are emitted by the transmitting module in each measurement cycle. Some laser pulses have greater energy, and some laser pulses have smaller energy. Laser pulses with larger energy can still have greater energy after propagation attenuation, so that they are easier to be captured by the receiving module, which can improve the long-range detection capability and accuracy. Pulses with smaller energy can make the reflected laser pulses not exceed the dynamic range of the receiving module, thereby reducing saturation, which can improve the close-range detection capability and accuracy, and realize the enhancement of the radar dynamic range. The receiving module obtains more accurate distance information of the target object in the target space based on the laser pulses received in each measurement cycle.

[0026] In a fourth aspect, the present application provides an electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the control method of the laser radar system as described in the second aspect above is implemented.

[0027] In a fifth aspect, the present application provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the control method of the laser radar system as described in the second aspect above.

[0028] In a sixth aspect, the present application provides a computer program product, comprising a computer program, which, when executed by a processor, implements the control method of the laser radar system as described in the second aspect above.

[0029] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0031] Figure 1 This is one of the structural diagrams of the laser radar system provided in the embodiment of the present application;

[0032] Figure 2 This is the second structural diagram of the laser radar system provided in the embodiment of the present application;

[0033] Figure 3 is a schematic diagram of a laser pulse emitted by a transmitting module in the related art;

[0034] Figure 4 is a schematic diagram of a laser pulse emitted by a transmitting module provided in an embodiment of the present application;

[0035] Figure 5 Schematic diagram of the measurement delay of each measurement cycle provided in an embodiment of the present application;

[0036] Figure 6 is a schematic diagram of the superposition of histograms provided in the embodiments of the present application;

[0037] Figure 7 1 is a schematic diagram of the structure of the bias circuit in the receiving module provided in an embodiment of the present application;

[0038] Figure 8 is a schematic diagram of adjusting the reverse bias voltage of a receiving module provided in an embodiment of the present application;

[0039] Figure 9 1 is a flow chart of a control method for a laser radar system provided in an embodiment of the present application;

[0040] Figure 10 It is a structural diagram of an electronic device provided in an embodiment of the present application.

[0041] Reference numerals:

[0042] LiDAR system 100, transmitting module 110, receiving module 120, transceiver control module 130,

[0043] Laser driving module 140 , scanning module 150 , and data processing module 160 . DETAILED DESCRIPTION

[0044] The following will be combined with the accompanying drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the embodiments described are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of this application.

[0045] The terms "first," "second," and the like in the specification and claims of this application are used to distinguish similar objects, and are not used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of this application can be implemented in an order other than that illustrated or described herein, and that the objects distinguished by "first," "second," and the like are generally of the same type, and do not limit the number of objects; for example, the first object can be one or more. In addition, the term "and / or" in the specification and claims refers to at least one of the connected objects, and the character " / " generally indicates that the objects connected are in an "or" relationship.

[0046] Below, in conjunction with the accompanying drawings, the laser radar system 100, the control method of the laser radar system 100, the vehicle, the electronic device and the readable storage medium provided in the embodiments of the present application are described in detail through specific embodiments and their application scenarios.

[0047] like Figure 1 As shown, the lidar system 100 includes a transmitting module 110 and a receiving module 120 .

[0048] The transmitting module 110 is a module that can transmit laser pulses, and the receiving module 120 is a module that can receive laser pulses.

[0049] In this embodiment, the transmitting module 110 is configured to transmit laser pulses with different amplitudes to the target space within multiple measurement cycles.

[0050] The receiving module 120 is configured to receive laser pulses reflected from the target space in each measurement cycle, and obtain distance information of the target object in the target space based on the laser pulses received in each measurement cycle.

[0051] The target space may be any space. For example, the laser radar system 100 may be installed on a vehicle, and the target space may be the space corresponding to the front of the vehicle.

[0052] The target space may include target objects and other objects. The target objects are objects to be detected for distance, and other objects are objects that may interfere with the detection of the distance to the target objects. For example, the target objects may be buildings, and other objects may be dust, raindrops, etc.

[0053] The distance information may include the distance of the target object relative to the lidar system 100.

[0054] In this embodiment, the laser radar system 100 is used to detect the distance information of the target object. The process of the laser radar system 100 performing distance information detection can be divided into multiple measurement cycles. In each measurement cycle, a beam of laser pulses is emitted by the transmitting module 110, and the laser pulses reflected back from the target space are captured by the receiving module 120.

[0055] It can be understood that the transmitting module 110 transmits laser pulses to the target space, and the laser pulses received by the receiving module 120 may include laser pulses reflected by the target object and other objects.

[0056] The time-correlated single-photon counting method (TCSPC) can be used to count the time distribution of photons arriving at the receiving module 120 to form a histogram. The histogram can reflect the distribution of the number of photons detected at different time points. The horizontal axis of the histogram represents time, and the vertical axis represents the number of photons detected within a specific time interval.

[0057] In each measurement cycle, a laser pulse is emitted and the moment of the returned photon is recorded. Each measurement cycle corresponds to a histogram. By superimposing the various histograms, a histogram reflecting the overall distribution of the photon return time corresponding to the distance detection performed by the laser radar system 100 can be obtained. The superimposed histogram is peak-fitted to obtain the distance information of the target object.

[0058] It should be noted that the amplitude of the laser pulse emitted by the transmitting module 110 in each measurement cycle is different. In the overall laser pulse sequence, some laser pulses have greater energy and some laser pulses have less energy. The pulses with greater energy can improve the long-range detection capability and accuracy, and the pulses with less energy can improve the short-range detection capability and accuracy, thereby enhancing the dynamic range of the radar.

[0059] In related technologies, lidar usually has a small dynamic range, and it is difficult to simultaneously take into account the measurement accuracy of short and long distances.

[0060] According to the laser radar system 100 provided in the embodiment of the present application, laser pulses with different amplitudes are emitted in each measurement cycle through the transmitting module 110. Some laser pulses have greater energy, and some laser pulses have less energy. Laser pulses with greater energy can still have greater energy after propagation attenuation, so that they are more easily captured by the receiving module 120, which can improve the long-range detection capability and accuracy. Pulses with smaller energy can make the reflected laser pulses not exceed the dynamic range of the receiving module 120, thereby reducing saturation, improving the close-range detection capability and accuracy, and realizing the enhancement of the radar dynamic range. The receiving module 120 obtains more accurate distance information of the target object in the target space based on the laser pulses received in each measurement cycle.

[0061] In some embodiments, the transmitting module 110 is configured to transmit laser pulses with increasing and / or decreasing amplitudes toward the target space.

[0062] In this embodiment, the laser radar system 100 may emit laser pulses with increasing amplitude, or emit laser pulses with decreasing amplitude, or emit laser pulses with alternating increasing and decreasing amplitudes toward the target space during a distance information detection process.

[0063] Laser pulses with orderly amplitude changes are easier to filter out random noise than laser pulses with random amplitude changes, thereby improving the quality of the pulse signal.

[0064] In some embodiments, the measurement delay of each measurement cycle is different, and the measurement delay is the time interval between the moment when the transmitting module 110 transmits the laser pulse and the moment when the receiving module 120 receives the laser pulse.

[0065] In related art, after the transmitting module 110 transmits a laser pulse, the receiving module 120 is usually turned on synchronously for detection. Usually, in each measurement cycle, the time delay of receiving the laser pulse relative to the laser pulse emission is fixed.

[0066] In an embodiment of the present application, the non-fixed measurement delay can reduce the accumulation of laser pulses reflected in each measurement cycle within a fixed time window. When the histograms are superimposed, the same time length areas of each histogram can form an interlaced distribution, making the peak of the superimposed histogram more obvious, thereby improving the accuracy of the detection distance information.

[0067] In some embodiments, the receiving module 120 is used to form histogram data based on the laser pulses received within the measurement period, and based on the moment when the transmitting module 110 transmits the laser pulse, the histogram data within each measurement period is interleaved and superimposed to obtain a target histogram, and distance information is obtained based on the target histogram.

[0068] Among them, the histogram data is used to count the distribution of the time when photons arrive at the receiving module 120 within a measurement cycle, and the target histogram is obtained by superimposing the various histogram data, which is used to reflect the overall distribution of the photon return time in the entire distance measurement process.

[0069] In this embodiment, the transmitting module 110 emits a laser pulse to the target space, and the time distribution of the photons arriving at the receiving module 120 can be counted by the time-correlated single-photon counting method to obtain histogram data. The histogram data can reflect the distribution of the number of photons detected at different time points. The horizontal axis of the histogram data represents time, and the vertical axis represents the number of photons detected within a specific time interval.

[0070] In each measurement cycle, a laser pulse is emitted and the moment of the returning photon is recorded. Each measurement cycle corresponds to a histogram data.

[0071] like Figure 6 As shown in the figure, T0 is the time when the transmitting module 110 transmits the laser pulse in each measurement cycle, SPAD_ON is the time when the receiving module 120 receives the laser pulse in each measurement cycle, and the histogram is calculated based on T0. Figure 1 -Histogram Figure 6 After alignment, they are superimposed to form a staggered superposition effect to obtain the target histogram, and the target histogram is peak-fitted to obtain the distance information of the target object.

[0072] In some embodiments, the transmitting module 110 is configured to transmit laser pulses at random moments within each measurement period, and / or the receiving module 120 is configured to receive laser pulses at random moments within each measurement period.

[0073] In the related art, usually, each measurement period corresponds to a fixed first reference time for emitting a laser pulse, and a fixed second reference time for receiving the laser pulse.

[0074] In this embodiment, the transmitting module 110 can transmit laser pulses at a random time before the first reference moment or a random time after the first reference moment, and the receiving module 120 can start receiving laser pulses at a random time before the second reference moment or a random time after the second reference moment, so that the measurement delay of each measurement cycle changes randomly.

[0075] It should be noted that the range of changes in the time of emitting laser pulses and the range of changes in the time of receiving laser pulses are relatively short relative to the duration of the entire measurement cycle, that is, the time of emitting laser pulses and the time of receiving laser pulses vary within a very short range, and the changes in the time of emitting laser pulses and the time of receiving laser pulses do not affect the normal detection function of the laser radar system 100.

[0076] In some embodiments, the receiving module 120 is configured to adjust the reverse bias voltage of its own photodiode during the process of receiving laser pulses to change the efficiency of receiving laser pulses.

[0077] Among them, the receiving module 120 may include a bias circuit, in which a photodiode is provided. The photodiode is used to receive photons and convert optical signals into electrical signals. The reverse bias is a voltage applied to the photodiode in the opposite direction to the forward conduction direction. The magnitude of the reverse bias affects the photon detection efficiency of the photodiode in the receiving module 120.

[0078] The photon detection efficiency of the photodiode increases with the increase of the reverse bias voltage, that is, for the same number of photons, a larger reverse bias voltage can bring a higher photon detection efficiency, that is, the efficiency of receiving laser pulses.

[0079] In this embodiment, the receiving module 120 continuously adjusts the reverse bias voltage of its own photodiode during the process of receiving laser pulses. The adjustment method can be linear, nonlinear, or even discontinuous.

[0080] The energy of the laser pulse reflected at a close distance is usually relatively large, and the ranging accuracy can be improved by a smaller reverse bias voltage. The energy of the laser pulse reflected at a long distance is usually relatively small, and the ranging accuracy can be improved by a larger reverse bias voltage, thereby enhancing the dynamic range of the radar and obtaining more accurate distance information.

[0081] In some embodiments, the reverse bias voltage changes in the same pattern in each measurement cycle.

[0082] In this embodiment, the reverse bias voltage changes in the same pattern in each measurement cycle, so that the measurement conditions in each measurement cycle are consistent, the fluctuation of the distance measurement result is reduced, and the distance information obtained is more accurate.

[0083] In some embodiments, the lidar system 100 is a single photon avalanche diode lidar system 100 .

[0084] The Single Photon Avalanche Diode (SPAD) laser radar system 100 has strong ranging capability, low cost and high system integration.

[0085] A specific embodiment of the laser radar system 100 is introduced below.

[0086] In this embodiment, the lidar system 100 is a single photon avalanche diode lidar system 100 .

[0087] like Figure 2As shown, the laser radar system 100 may include a transceiver control module 130 , a laser driving module 140 , a transmitting module 110 , a receiving module 120 and a scanning module 150 , and the receiving module 120 includes a data processing module 160 .

[0088] The transceiver control module 130 sends a laser emission signal to the laser driving module 140, and the laser driving module 140 injects current into the laser, i.e., the transmitting module 110, and the laser emits light, and the laser radar scans and emits the entire target space through the scanning module 150.

[0089] The transceiver control module 130 controls the timing logic and configuration parameters of the SPAD chip, i.e., the receiving module 120, to respond to the laser echo. The echo signal collected by the receiving module 120 is packaged into a point cloud output by the data processing module 160.

[0090] In related technologies, for measuring a target, a SPAD radar usually emits a set of light pulses. The SPAD chip repeatedly measures multiple echoes of the same target to generate a histogram, and then performs peak search and fitting on the histogram to achieve distance measurement of the target. The SPAD radar usually emits a set of laser pulses with the same amplitude and fixed period, such as Figure 3 As shown, the amplitudes of laser pulses Pulse1 to Pulse6 are the same, that is, the pulse energies are the same. SPAD laser radars usually have a small dynamic range, and it is difficult to take into account both short-range and long-range measurement accuracy at the same time.

[0091] In the embodiment of the present application, the laser radar system 100 can emit amplitude modulated laser pulses, such as Figure 4 As shown, in a group of laser pulse trains, laser pulse Pulse1 to laser pulse Pulse6, the pulse energy of each laser is different and can be gradually increased. Some of this group of laser pulse trains have large energy, and some have small energy. Larger laser pulses can improve long-range detection capabilities and accuracy, and smaller laser pulses can improve short-range detection accuracy, thereby enhancing the dynamic range of the radar. The specific laser amplitude modulation range can be designed according to the product requirements and system solutions of the radar.

[0092] In related technologies, usually after laser emission, the SPAD will be turned on synchronously for detection. The time when detection starts is the SPAD_ON time. Usually, for each detection, the delay of the SPAD_ON time relative to the laser emission is fixed.

[0093] In the embodiment of this application, Figure 5As shown, the radar dynamic range is improved by regulating the delay of the opening moment of the receiving module 120. After each laser emission, the receiving module 120 is turned on after an unfixed delay δt, that is, δt1-δt6 are different. When the histogram is accumulated after the detection is completed, as shown in FIG. Figure 6 As shown in the figure, taking the respective laser emission moments as the T0 moment of histogram accumulation can reduce the quantization error effect of the radar when the echo is strong and improve the detection accuracy.

[0094] The transceiver control module 130 achieves a high dynamic range of the laser radar system 100 by adjusting the reverse bias voltage of the photodiode in the receiving module 120 in real time in the time domain. It should be noted that the transceiver control module 130 can transmit a reverse bias voltage adjustment signal to the bias circuit of the receiving module 120 to adjust the reverse bias voltage of the photodiode, such as Figure 7 As shown, the bias circuit includes resistor R Q and photodiode, the transceiver control module 130 can adjust the reverse bias voltage V by adjusting Vop OUT .

[0095] like Figure 8 As shown, a measurement cycle of the receiving module 120 is the time from the TRG signal to the SPAD OFF signal. When the transceiver control module 130 sends the TRG signal and turns on the receiving module 120 for detection, the reverse bias voltage V of the photodiode is gradually increased synchronously. OUT , the adjustment method can be linear, nonlinear or even discontinuous.

[0096] The photon detection efficiency of the laser radar system 100 will increase with V OUT increases with the increase of V, that is, for the same number of photons, a larger V OUT It will bring greater photon detection efficiency. At close distances, when the echo is usually large, the smaller V OUT To ensure the ranging accuracy, use a larger V OUT Achieve stronger ranging capability and detection accuracy of the system.

[0097] In this embodiment, the power of each laser pulse in each group of laser pulse trains is not the same, but there are pulses with greater energy and pulses with less energy.

[0098] After each laser pulse of each detection group is emitted, the delay of the moment when this group of SPADs starts receiving is adjusted.

[0099] During one detection cycle of SPAD, the bias voltage V OP It is not fixed, but gradually increases V OP .

[0100] An embodiment of the present application also provides a control method for the laser radar system 100 , which is used to control the above-mentioned laser radar system 100 .

[0101] Among them, the control method of the laser radar system 100 can be applied to the terminal, and can be specifically executed by hardware or software in the terminal.

[0102] The control method of the laser radar system 100 provided in the embodiment of the present application can be executed by an electronic device or a functional module or functional entity in the electronic device that can implement the control method of the laser radar system 100. The control method of the laser radar system 100 provided in the embodiment of the present application is described below using the electronic device as an example of the execution body.

[0103] like Figure 9 As shown, the control method of the laser radar system 100 includes: step 910, step 920 and step 930.

[0104] Step 910: Control the transmitting module 110 to transmit laser pulses with different amplitudes to the target space within multiple measurement cycles.

[0105] Step 920 : Control the receiving module 120 to receive the laser pulse reflected by the target space in each measurement cycle, and obtain the distance information of the target object in the target space based on the laser pulse received in each measurement cycle.

[0106] According to the control method of the laser radar system 100 provided in the embodiment of the present application, laser pulses with different amplitudes are emitted by the transmitting module 110 in each measurement cycle. Some laser pulses have greater energy, and some laser pulses have less energy. The laser pulses with greater energy can still have greater energy after propagation attenuation, so that they are easier to be captured by the receiving module 120, which can improve the long-range detection capability and accuracy. The pulses with smaller energy can make the reflected laser pulses not exceed the dynamic range of the receiving module 120, thereby reducing saturation, improving the close-range detection capability and accuracy, and realizing the enhancement of the radar dynamic range. The receiving module 120 obtains more accurate distance information of the target object in the target space based on the laser pulses received in each measurement cycle.

[0107] In some embodiments, the measurement delay of each measurement cycle is different, and the measurement delay is the time interval between the moment when the transmitting module 110 transmits the laser pulse and the moment when the receiving module 120 receives the laser pulse.

[0108] In some embodiments, the method further comprises:

[0109] The control receiving module 120 adjusts the reverse bias voltage of its own photodiode during the process of receiving laser pulses to change the efficiency of receiving laser pulses.

[0110] A specific embodiment of a control method for the laser radar system 100 is introduced below.

[0111] In step 1, the laser radar system 100 prepares to start a distance detection, which is divided into N measurement cycles with a cycle length of T.

[0112] In step 2, the laser radar system 100 enters the first measurement cycle. Assuming that the absolute time is 0 at this time, during the first measurement cycle, the transceiver control module 130 sends a laser trigger signal TRG_Laser to the laser driving module 140. TRG_Laser describes the pulse energy E1 of the laser and the absolute time of laser emission.

[0113] Step 3: The transceiver control module 130 immediately sends a SPAD trigger signal TRG_SPAD to the receiving module 120. The measurement delay between TRG_SPAD and TRG_Laser is δt1. The receiving module 120 starts to detect the laser echo. This is the time T0 of SPAD detection. At the same time, the transceiver control module 130 starts to gradually increase the reverse bias voltage V of the photodiode. OP .

[0114] Step 4: After a period of time, the receiving module 120 completes the detection within its measurement range and turns off the receiving module 120.

[0115] Step 5: The data processing module 160 performs data processing on the echo signal received above.

[0116] In step six, the laser radar system 100 enters the second measurement cycle. At this time, the absolute time is T. The transceiver control module 130 sends a laser trigger signal to the laser driving module 140. The laser pulse has a different pulse energy E2.

[0117] Step 7: Repeat steps 3 to 5 to complete the second measurement cycle, wherein the measurement delay between TRG_SPAD and TRG_Laser is different δt2; wherein the VOP adjustment rule of the transceiver control module 130 should remain the same as that of the first measurement cycle.

[0118] Step 8: Repeat steps 6 and 7 multiple times, with each measurement having a different laser pulse energy E and a different SPAD_ON measurement delay δt.

[0119] Step 9: The laser radar system 100 enters the Nth measurement cycle, at which time the laser pulse energy is E N, the absolute time of SPAD_ON is ((N-1)*T+δt N ).

[0120] Step 10: The laser radar system 100 completes the Nth measurement cycle according to steps 3 and 4.

[0121] In step 11, the laser radar system 100 accumulates histograms. These histograms uniformly use the TRG_Laser moment as the detection time T0, rather than the TRG_SPAD moment. The accumulated histograms are used for peak search and distance calculation to complete this distance detection.

[0122] For the SPAD trigger signal SPAD_ON measurement delay description (δt1, δt2, ..., δt N ), each value should be kept different as much as possible, for the emission energy description of the laser trigger signal (E1, E2, ..., E N ), should cover a larger range of variation, for corresponding to the measurement of different distance ranges, the transceiver control module 130 for V OP The adjustment rules remain the same.

[0123] It should be noted that when laser pulses of the same amplitude are emitted to the target space within multiple measurement cycles, the dynamic range of the radar can be improved by separately implementing different measurement delays for each measurement cycle, or by adjusting the reverse bias voltage of the photodiode during the process of receiving the laser pulses.

[0124] The control method of the laser radar system 100 provided in the embodiment of the present application can be executed by the control device of the laser radar system 100. In the embodiment of the present application, the control device of the laser radar system 100 is used as an example to illustrate the control method of the laser radar system 100 provided in the embodiment of the present application.

[0125] An embodiment of the present application also provides a control device for the laser radar system 100.

[0126] The control device of the laser radar system 100 includes:

[0127] A first processing module is used to control the transmitting module 110 to transmit laser pulses with different amplitudes to the target space within multiple measurement cycles;

[0128] The second processing module is used to control the receiving module 120 to receive the laser pulse reflected by the target space in each measurement cycle, and obtain the distance information of the target object in the target space based on the laser pulse received in each measurement cycle.

[0129] According to the control device of the laser radar system 100 provided in the embodiment of the present application, laser pulses with different amplitudes are emitted in each measurement cycle through the transmitting module 110. Some laser pulses have greater energy, and some laser pulses have less energy. The laser pulses with greater energy can still have greater energy after propagation attenuation, so that they are more easily captured by the receiving module 120, which can improve the long-range detection capability and accuracy. The pulses with smaller energy can make the reflected laser pulses not exceed the dynamic range of the receiving module 120, thereby reducing saturation, improving the close-range detection capability and accuracy, and realizing the enhancement of the radar dynamic range. The receiving module 120 obtains more accurate distance information of the target object in the target space based on the laser pulses received in each measurement cycle.

[0130] In some embodiments, the measurement delay of each measurement cycle is different, and the measurement delay is the time interval between the moment when the transmitting module 110 transmits the laser pulse and the moment when the receiving module 120 receives the laser pulse.

[0131] In some embodiments, the second processing module is further configured to control the receiving module 120 to adjust the reverse bias voltage of its own photodiode during the process of receiving the laser pulse, so as to change the efficiency of receiving the laser pulse.

[0132] The control device of the laser radar system 100 in the embodiment of the present application can be an electronic device or a component in the electronic device, such as an integrated circuit or a chip. The electronic device can be a terminal or other devices other than a terminal.

[0133] The control device of the laser radar system 100 in the embodiment of the present application can be a device having an operating system. The operating system can be an Android operating system, an iOS operating system, or other possible operating systems, which are not specifically limited in the embodiment of the present application.

[0134] The control device of the laser radar system 100 provided in the embodiment of the present application can achieve Figure 9 To avoid repetition, the various processes implemented in the method embodiment are not described here.

[0135] An embodiment of the present application also provides a vehicle.

[0136] The vehicle includes a lidar system 100 as described above.

[0137] According to the vehicle provided in the embodiment of the present application, laser pulses with different amplitudes are emitted in each measurement cycle through the transmitting module 110. Some laser pulses have greater energy, and some laser pulses have less energy. The laser pulses with greater energy can still have greater energy after propagation attenuation, so that they are more easily captured by the receiving module 120, which can improve the long-range detection capability and accuracy. The pulses with smaller energy can make the reflected laser pulses not exceed the dynamic range of the receiving module 120, thereby reducing saturation, improving the close-range detection capability and accuracy, and realizing the enhancement of the radar dynamic range. The receiving module 120 obtains more accurate distance information of the target object in the target space based on the laser pulses received in each measurement cycle.

[0138] In some embodiments, as Figure 10 As shown, an embodiment of the present application also provides an electronic device 1000, including a processor 1001, a memory 1002, and a computer program stored in the memory 1002 and executable on the processor 1001. When the program is executed by the processor 1001, each process of the control method embodiment of the above-mentioned laser radar system 100 is implemented, and the same technical effect can be achieved. To avoid repetition, it will not be described here.

[0139] It should be noted that the electronic devices in the embodiments of the present application include the mobile electronic devices and non-mobile electronic devices mentioned above.

[0140] An embodiment of the present application also provides a non-transitory computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, it implements the various processes of the control method embodiment of the above-mentioned lidar system 100 and can achieve the same technical effect. To avoid repetition, it will not be repeated here.

[0141] The processor is the processor in the electronic device described in the above embodiment. The readable storage medium includes a computer readable storage medium, such as a computer read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0142] An embodiment of the present application also provides a computer program product, including a computer program, which implements the control method of the above-mentioned lidar system 100 when executed by a processor.

[0143] The processor is the processor in the electronic device described in the above embodiment. The readable storage medium includes a computer readable storage medium, such as a computer read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0144] An embodiment of the present application further provides a chip, which includes a processor and a communication interface, wherein the communication interface is coupled to the processor, and the processor is used to run programs or instructions to implement the various processes of the control method embodiment of the above-mentioned lidar system 100, and can achieve the same technical effect. To avoid repetition, it will not be repeated here.

[0145] It should be understood that the chip mentioned in the embodiments of the present application can also be called a system-level chip, a system chip, a chip system or a system-on-chip chip, etc.

[0146] It should be noted that, in this article, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element. In addition, it should be noted that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in the opposite order according to the functions involved. For example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0147] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus the necessary general hardware platform, and of course can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art can be embodied in the form of a computer software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), including a number of instructions for enabling a terminal (which can be a mobile phone, computer, server, or network device, etc.) to execute the methods described in each embodiment of the present application.

[0148] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of this application, ordinary technicians in this field can also make many forms without departing from the purpose of this application and the scope of protection of the claims, all of which are within the protection of this application.

[0149] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0150] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and intent of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A laser radar system, characterized in that: include: A transmitting module, used for transmitting laser pulses with different amplitudes to the target space within multiple measurement cycles; A receiving module is configured to receive the laser pulse reflected by the target space in each measurement cycle, and obtain distance information of the target object in the target space based on the laser pulse received in each measurement cycle.

2. The laser radar system according to claim 1, characterized in that The transmitting module is used to transmit the laser pulses with increasing and / or decreasing amplitudes toward the target space.

3. The laser radar system according to claim 1 or 2, characterized in that The measurement delay of each measurement cycle is different, and the measurement delay is the time interval between the moment when the transmitting module transmits the laser pulse and the moment when the receiving module receives the laser pulse.

4. The laser radar system according to claim 3, characterized in that The receiving module is used to form histogram data based on the laser pulses received in the measurement period, and to obtain a target histogram by interleaving and superimposing the histogram data in each measurement period based on the moment when the transmitting module transmits the laser pulse, and to obtain the distance information based on the target histogram.

5. The laser radar system according to claim 3, characterized in that The transmitting module is used to transmit the laser pulse at a random moment in each measurement cycle, and / or the receiving module is used to receive the laser pulse at a random moment in each measurement cycle.

6. The laser radar system according to claim 1 or 2, characterized in that: The receiving module is used to adjust the reverse bias voltage of its own photodiode during the process of receiving the laser pulse.

7. The laser radar system according to claim 6, characterized in that The reverse bias voltage changes in the same manner in each measurement cycle.

8. The laser radar system according to any one of claims 1 to 7, characterized in that: The laser radar system is a single photon avalanche diode laser radar system.

9. A control method for a laser radar system according to any one of claims 1 to 8, characterized in that: include: Controlling the transmitting module to transmit laser pulses with different amplitudes to the target space within multiple measurement cycles; The control receiving module receives the laser pulse reflected by the target space in each measurement cycle, and obtains distance information of the target object in the target space based on the laser pulse received in each measurement cycle.

10. The control method of the laser radar system according to claim 9, characterized in that: The measurement delay of each measurement cycle is different, and the measurement delay is the time interval between the moment when the transmitting module transmits the laser pulse and the moment when the receiving module receives the laser pulse.

11. The control method of the laser radar system according to claim 9, characterized in that: The method further comprises: The receiving module is controlled to adjust the reverse bias voltage of its own photodiode during the process of receiving the laser pulse.

12. A vehicle, characterized in that: include: A laser radar system as claimed in any one of claims 1 to 8.

13. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the control method of the laser radar system as described in any one of claims 9 to 11 is implemented.

14. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the control method of the laser radar system as described in any one of claims 9 to 11 is implemented.

15. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the control method of the laser radar system as described in any one of claims 9 to 11 is implemented.

Images